Steering Position Sensor & now Yaw Rate Sensor

[swimrr]

Just a quick shout out to everyone who posted the amazing information in this thread. I'm contemplating taking out my dash to preemptively replace the heater core and have always read that one has to be careful with the clock spring. Knowing that there are fixes and workarounds out there and a still active group forum is very encouraging.

Thanks everyone!!!

[Endopotential]

First off, big thanks to @bigfoot_ev for holding my hand and talking me through this process. A couple things I learned, to add for whoever else follows:

- If like me, you've never worked on taking a steering wheel apart before, I found it hard to turn the wheel on a concrete driveway with the battery disconnected and the power steering pump nonfunctional. So lift up the front end with some jack stands and it's easy.

- Taking the clockspring off of the SAS/steering angle sensor is easy by prying up on the plastic tabs

- To be paranoid, as soon as the clockspring comes off, put a piece of tape around the perimeter so that it can't turn on itself and throw things off

- But removing the SAS from the steering column had me stumped for a bit.
Don't pry straight up as in the first picture, or you'll break the tab. If you look real closely, each tab sits very flush with shelf below it. Wedge a small screwdriver blade into the gap FROM THE SIDE for each of the two tabs on top, and the SAS slides off easily

- About that black cogwheel with the magnet and yellow paint marking, does anyone know what it does or how it functions?
It cog teeth don't seem to mate to anything, and that magnet throws off the balance point such that I had trouble keeping it at the 12 o'clock position during the reassembly process. I ended up using a small but very strong magnet on the outside to keep that cog in place during reassembly, then removed the magnet. Maybe the clockspring has a magnet in it to pair up with the cog?

At 130k miles, my circuit board thankfully still looked pristine. Hopefully this will be good preventative maintenance. I would get a random ABS/traction control dash light from out of the blue sometimes. Curious to see if it will go away after this.
BTW I didn't need VCDS or any reprogramming/alignment after this process, and van seems to steer just fine during the 3 mile test drive.

[dsheon]

Gave my highly tested sensor to the mechanic to reinstall, as I don't have those skills. He did all the turns to the left/right and lined it up. They say the part is no good.
Despite testing every trace and solder joint w multimeter - all good.
It shows 0000 so it's reading initially but won't take any codes and doesn't change when the wheel is turned. He thinks its the actual sensor and that it's just failing now. So it's important to pass on that these can go bad and have nothing to do with traces being worn out.

[dsheon]

[quote="owokie"]

[owokie]

[dsheon]

No. You're wasting your time without pulling the damn code. Even if the entire unit is dead, vag-com will tell you that with a "no comms" code.

I appreciate that but here's the situation. A friend who built circuits for Apple has the devices and is going through it - so I can't put it in the van and get a code at present. And when I ask my mechanic for the code they saw, I am told the sensor is "completely dead" - not exactly answering my question. In fairness, it's been a year since they did that diagnosis. But it's interesting I've been driving on it dead for a year and there is no sign of traces warn; and extensive multimeter testing comes back that everything is fine.

I'll take it back soon and we'll plug it in and see if they get a code. I have an OBD Fusion and got no codes when everything was assembled. Horn worked and no airbag notice.

So I do think that melted pad on the sensor makes sense but we'll try again and get the code if any from the mechanic. He told me "we've seen this before, you either need to replace it or use the online hack from Samba."

[owokie]

[dsheon]

Hello,
Updating on my little steering angle sensor mystery.
The traces are all in tact and tested on multimeter.

However, the little wedge shaped pad that sits atop the sensor wheel and rubs against the copper ring has warn. I believe a fingerprint (probably from the factory) on the copper ring was perfectly aligned with the pad and over time oil from that fingerprint dissolved the pad. When I opened the spring there was a black smudge on the copper immediately where it meets the pad. And little pencil-erasure like shavings were inside the device.
Photos - see the second page at about 1 o'clock you can see the smudge. I cleaned it with rubbing alcohol but on page 1 you can see the pad looks warn.
https://docs.google.com/document/d/16R2XLPrQxe9ORBhStKrWIED6imh-Gm6dFoKgjBrlV3E/edit?usp=sharing

Does anyone by any chance know if that pad conducts electricity and/or have suggestions for material to use to replace it? Or maybe go without it and I suspect the device will be louder? Given the traces were solid this explanation - that the pad was sticking/melting over time due to a fingerprint, while unusual, seems possible. Thoughts?

[dsheon]

Thanks for that explanation.
I would post a better photo but I have a guy working on the sensor/PCB using a multimeter to find any shorts. He says it's working perfectly though and can't find any issues.
I spoke with the mechanic, or had an exchange with him. He said there are no codes from the sensor - it wasn't working at all, completely dead.
I have a new theory. the Sensor "wheel" that aligns with the eye has a triangular shaped "wedge" on top that looks to have spongy material. I would describe the material as similar to the thin foam in a soft packing envelope.
That may have disintegrated a bit. You can kind of see it in my photo/google doc. When I opened the clockspring there was considerable dark dust/debris that could have come from that. And on the copper disk side there was a sticky smudge directly over it - as though it over heated and melted. I could see a finger print there - likely from when it was installed. I wonder if oil from a finger may have eventually accelerated some sort of burning. I have it all cleaned up but wonder if I should attempt to replace the remaining "foam" and if so what I should use. Any reactions to that? We will fix some of the traces that have slight damage though they still carry load. And I will insert the plastic ring.

[bigfoot_ev]

[dsheon]

Bigfoot - wow thank you. My only question (for now). When you say to give two turns to the right and two to left, can you provide context for that? Am I to turn the little gear with the yellow paint twice in either direction before putting the painted part into the eye as you note, or is the the copper sensor? Just a little confused. Will try next to paste the photo directly here. Update: a friend with a multimeter has tested the traces and we can't find a problem! Not really sure what to do other than paint w nailpolish and insert the plastic ring (because wny not)

[vwplenty]

Here is a clear picture of the clockspring traces.

Cheers,
Robert

This one with a cover over the traces cut from a 3m electrical tape box of PP5 polypropylene.

[samba415]

Zero need to apologize. I'll keep searching. When I find one, I'll post it and folks here can do for themselves.
_________________
Old stable: '63 Baja, '69 Square, '72 Bug, '65 & '67 Samba, '73 412 wagon & 2dr 4spd

Current: '04 Golf TDI, '03 Weekender

[bigfoot_ev]

Sorry, I didn't get a straight on picture before I glued the plastic in place. I was also going to link to dsheon's post. Maybe he has a higher resolution pic he could post instead of posting it via a google doc.

[samba415]

From Dave Sheon's other thread:

https://docs.google.com/document/d/16R2XLPrQxe9ORBhStKrWIED6imh-Gm6dFoKgjBrlV3E/edit

Found that.... It's a start, but the "9am to 12pm" of the clock spring board is blown out a touch. BigfootEv's third pic in the thread is money on the detail but misses that area.

I've noticed the rebuild outfit in Germany (KFZ) I linked in the thread here has raised their rebuild prices. Seems they've caught on to this captive market. Wreckers here in NA are/were selling (when available) pulled ESP units for $650-$850 pricing with "coin-flip" results for the buyers. KFZ may have seen that.
_________________
Old stable: '63 Baja, '69 Square, '72 Bug, '65 & '67 Samba, '73 412 wagon & 2dr 4spd

Current: '04 Golf TDI, '03 Weekender

[owokie]

[Endopotential]

[samba415]

Amazing! This is deeply appreciated. This will go a long way to enable the work we need to do. I was wondering if you took more pictures of your logic board for those of us with worn traces.

I was getting up the courage for a repair like the fella in eastern Europe but can't find a clean picture of the logic board without worn traces. I'm good and steady (for the moment) with a soldering iron, but I think my eyes need some assistance of the original logic board for reassurance. If not, that's OK.

I'll put this out in the interwebs and universe now...a clear picture of the logic board would help those of us who need visual reassurances of the original layout. Most close pics I've found are of boards that are worn out.
_________________
Old stable: '63 Baja, '69 Square, '72 Bug, '65 & '67 Samba, '73 412 wagon & 2dr 4spd

Current: '04 Golf TDI, '03 Weekender

[[email protected]]

This is the way
_________________
2001 eurovn weekender 207k fresh batteries

[bigfoot_ev]